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Found a cracked trace on a router board that no one spotted for 2 repair cycles
Had this Netgear router come back twice from a shop in Oklahoma City, both times with the same intermittent WiFi dropout. First tech reflowed the RF section, second swapped the caps, still acted up. I was about to give up when I ran a high-res scan with my 10x loupe and saw this hairline crack running under the antenna connector pad. Ten minutes with a jumper wire and it's been solid for 3 days of burn-in. Makes me wonder how many boards get tossed for something this simple. Has anyone else found success with visual inspections over component swaps on tricky intermittent faults?
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drews555d ago
Do you really find cracked traces in a quarter of intermittent faults, though? In my experience, most of those come from bad solder joints on connectors or failed capacitors that test fine on a meter but die under load. That hairline crack under the antenna pad is a good find, sure, but I've spent hours chasing a phantom line with a loupe only to end up swapping a regulator that was dropping out at temperature. I'll do a quick visual pass first thing, but I honestly trust a good thermal cycle and a scope more than my eyes for the sneaky ones.
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kellyallen5d ago
Man, that's the classic one right there! I've had almost the same thing happen on an old Asus router where the board flexed just enough around the USB port that the trace lifted under the solder mask. Spent two weekends swapping power regulators before I finally saw the thin line with a bright light at the right angle. Once you start looking for cracked traces instead of bad components, you'll find them in a quarter of the intermittent stuff you see. A quick continuity test between the pad and the nearest via would've caught it in about 60 seconds if the first tech had known to do it. That jumper wire trick has saved me more boards than any rework station I own. You still hit those days where a simple visual check with a magnifying lamp beats everything else on the bench?
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